A high-resolution map of reactive nitrogen inputs to China

Area of Science:

• Environmental Science
• Ecology
• Agricultural Science

Background:

• Reactive nitrogen (Nr) inputs to China's environment have risen significantly over the past century due to increased food demand.
• China's reactive nitrogen emissions constitute over one-third of the global total, causing substantial environmental pollution and health issues.
• Understanding the spatial distribution of Nr inputs is vital for targeted pollution mitigation strategies.

Purpose of the Study:

• To develop a high-resolution (1 km × 1 km) database of reactive nitrogen inputs in China for the year 2017.
• To identify regional hotspots and land use types with high Nr inputs.
• To provide essential data for environmental health research and global change modeling.

Main Methods:

• Utilized the CHANS model to compile a comprehensive database of Nr inputs.
• Considered various land use types and reactive nitrogen sources.
• Achieved a spatial resolution of 1 km × 1 km for detailed analysis.

Main Results:

• Identified the North China Plain, Sichuan Basin, and Middle-Lower Yangtze River Plain as major hotspots for Nr inputs.
• Observed per-hectare Nr inputs in hotspots to be an order of magnitude higher than in other regions.
• Determined that cropland and surface water bodies receive significantly higher Nr inputs compared to other land uses.

Conclusions:

• The developed database offers unprecedented spatial detail on reactive nitrogen inputs across China.
• The identified hotspots and land use patterns highlight critical areas for pollution control interventions.
• This resource is crucial for advancing research in environmental health and global change modeling.